Splicing of textile strands



Aug. 25, 1970 M. F. IRWIN 3,525,207

SPLICING OF TEXTILE STRANDS Filed Oct. 14, 1968 SPLICING D WING -j M SPL\C\NG /I/ PREDRAWN END UNDRAWN END DRAWING cmm me #VVE/VTOR MALCOLM F. IRWIN nited States Patent W US. Cl. 57-142 19 Claims ABSTRACT OF THE DISCLOSURE Textile strands drawable to increased length are spliced end to end, as by a fluid-splicing technique, following predrawing of the end portion of one of the strands.

Reference is made to my copending patent applications (filed jointly with a coinventor) Ser. No. 645,410 filed June 12, 1967, now Pat. 3,407,583, and Ser. No. 729,819, filed May 16, 1968, now Pat. 3,461,661, the contents of which are incorporated herein by such reference, to the extent not explicitly set forth below.

The referenced applications disclose an improved fluidsplicing technique, most commonly using air as the splicing fluid. Air is rotated circumferentially of the overlapped strand portions to be spliced,'thereby false-twisting them in opposite directions longitudinally from an intermediate locus thereon, and Swirling filaments from each strand portion into interengagement with filaments from the other strand portion at locations flanking the intermediate locus, at which there is a resulting twist reversal and greater interfilament spacing than at the flanking locations.

Fluid-splicing techniques of other types are disclosed by Gonsalves in Pat. 3,273,330; Rosenstein in Pat. 3,306,- 020; Dodson et al. in Pat. 3,339,362; Gemeinhardt in Pat. 3,345,809; and Iwnicki in Brit. Pat. 956,992.

Regardless of the relative merits of the mentioned or other fluid-splicing methods in splicing strands of drawn or undrawable filaments, when they are used on strands of filaments drawable to increased length the security of the splice is threatened, especially during any subsequent processing step in which drawing occurs. It will be recognized that, during drawing, the length increase is accompanied by attenuation to decreased diameter, and both effects are conducive to disengagement of the spliced strands.

A principal object of the present invention is provision of an improved splice of undrawn textile strands composed of drawable filaments.

Another object is modification of fluid-splicing techniques for use with undrawn textile strands.

A further object is continuous drawing or draw-crimping of drawable textile strands of finite length spliced end to end.

Other objects of this invention, together with means and methods for accomplishing the various objects, will be apparent from the following description and the accompanying diagrams.

FIG. 1 is a block diagram of the flow or passage of undrawn textile strands through steps of splicing and drawing;

FIG. 2 is a block diagram of the juxtaposed or overlapped end portions of strands to be spliced; and

FIG. 3 is a schematic diagram of succeeding drawing and crimping steps or a composite draw-crimping of textile strands.

In general, the objects of this invention are accomplished to provide a splice of undrawn strands wherein the spliced portion of one of the strands is predrawn to permanently increased length.

3,525,207 Patented Aug. 25, 1970 FIG. 1 shows drawable textile strand 1 passing through splicing and drawing steps in succession. It will be understood that the strand so designated is made up of a succession of strand increments of finite length joined end to end but that no attempt is made to indicate the spliced junctions.

FIG. 2 shows schematically the splicing step performed on strand increments 1 and 1" located in that order as components of overall strand 1. The adjacent terminal or end portions of the respective strand or, more precisely, strand increments are juxtaposed in overlapping relationship to one another and spliced together. The visible end portion of preceding strand increment 1' is indicated as undrawn, whereas the visible end portion of following strand increment 1" is indicated as having been predrawn.

The actual splicing may be accomplished in any suitable manner, as indicated previously. The predrawing of the indicated terminal portion of one strand increment is not illustrated because it can be accomplished manually or in any other desired manner. Thus, the strand end can be gripped securely between thumb and forefinger of one hand and be pulled against restraint suitably applied, as by the thumb and forefinger of the opposite hand, to a portion thereof spaced appropriately from the end. The amount or degree of draw will be the maximum of which the filamentary strand composition is capable, usually on the order of four to eight times the original length, i.e., 4X to 8X draw. When the drawing is done manually it is easy to feel the abrupt increase in tensile modulus at the drawing limit, when the elastic modulus is encountered.

In practice, the strand to be drawn may be supplied as individual strands or strand increments wound on individual bobbins or similar packages from which it is unwound. The exposed or outside end of a packaged strand not yet being processed may be drawn manually and then be juxtaposed manually in overlapping relationship to the undrawn tail end of an unwinding strand, whereupon the two strand ends are spliced together. The presence of the drawn strand portion throughout the length of the splice prevents the undrawn end portion spliced thereto from being drawn in the subsequent drawing step. Consequently, the security of the splice is not disturbed as it might or would have been had both spliced end portions been drawable to increased length and attenuated diameter, after splicing.

While useful generally in operations involving strand drawing, the present invention is particularly useful in processes involving crimping as well. FIG. 3 shows schematically drawing and stuifer-crimping of textile strand 1. The strand passes over successive pairs of godet rolls 2, 3, and 4, 5 and is drawn therebetween. From the second pair of godets the strand passes between the nip of pair of feed rolls 6, 7 and into stufi'ing chamber 8, from which it is withdrawn by any suitable means, such as windup rolls (not shown). Shown only schematically, the indicated stutter crimper may be of the type disclosed in my Pats. 3,279,025 and 3,386,142 (both filed jointly with a co-inventor), Stanley Pat. 3,348,283 and patents mentioned therein, or other stufier crimper. Of course, the splice of this invention is useful in any draw-crimping operation, i.e., wherever the strand is drawn and crimped either simultaneously or in prompt succession regardless of the type of crimping. See, for example, Stanley Pats. 3,374,302 and 3,376,622 for disclosures of simultaneous and successive draw-crimping techniques, respectively.

Perhaps the most common drawable strand compositions are the nylons (polycarbonamides), e.g., 66-nylon (i.e., polyhexamethylene adipamide), also 6-nylon, 11- nylon, 6l0-nylon, and fiber-forming copolymers thereof,

including terpolymers. Other suitable polymeric materials for strands to be treated according to this invention, including crimping as well as drawing of spliced strand, include most of the thermoplastic fiber-forming materials, such as polyhydrocarbons (e.g., polyethylene, polypropylene), polyesters (e.g., polyethylene terephthalate), polyacrylonitrile and copolymers of acrylontrile with other vinyl compounds, also copolyrners of vinyl chloride and vinylidene chloride, and polyurethanes. This list is simply exemplary, rather than intended to be exhaustive, of suitable compositions, most or all of which have low frictional coefiicients and, thus, tend to become unspliced, especially when spliced in undrawn condition. However, when strands so composed are spliced according to the present invention, they are securely bound together without adverse effect upon subsequent processing thereof. Of course, heating or even chemical plasticization may be desirable or prerequisite to drawing of strands formed of certain compositions, as is well known.

Although the illustration and foregoing description have indicated that the leading end of a following or succeeding strand is predrawn for splicing with the trailing end of a preceding strand, it will be apparent that the trailing end of the preceding strand can be predrawn instead thereof or in addition thereto. Indeed, both ends of any strand increment may be predrawn, and adjacent ends of preceding and following strand increments be left un drawn or predrawn, as desired. The rest of each strand increment will be undrawn, by which is meant that it is capable of being drawn in an ensuing drawing step, whether or not already partially drawn beyond its as-produced condition in which the component polymer molecules are relatively unoriented.

Notwithstanding the foregoing, it will be understood that other modifications can be made in the disclosed apparatus, process, and product, as by addition, combination, or division of parts or steps, while maintaining at least some of the advantages and benefits of the present invention, which is defined in the following claims.

The claimed invention:

1. Splice of at least two textile strands drawable to permanently increased length, wherein the spliced portion of only one of the mentioned strands is predrawn.

2. Splice of textile strands according to claim 1, wherein substantially all the rest of the strand having the predrawn portion is drawable to permanently increased length.

3. Splice of textile strands according to claim 2, wherein the other of the mentioned two strands is drawable to permanently increased length throughout substantially its entire length.

4. Textile strand splice of at least two twisted multifilament strands drawable to permanently increased length, the spliced part of only one of the mentioned strands being predrawn and thus not drawable to increased length, the splice having substantially constant diameter throughout and having an intermediate portion characterized by a twist discontinuity.

5. Textile strand splice according to claim 4, wherein the intermediate portion of the splice is characterized by greater interfilament spacing than present in the portions flanking the intermediate spacing.

6. Textile strand splice according to claim 4, wherein the portions flanking the intermediate portion exhibit oppositely directed twist.

7. In fluid splicing of at least two textile strands, the improvement comprising predrawing a length increment of only one of the mentioned strands to permanently in- 4 creased length and then including the predrawn length increment in the resulting splice.

8. Process according to claim 7, wherein the predrawn length increment is substantially as long as the resulting splice.

9. Process according to claim 7, wherein the predrawn length increment comprises a terminal portion of that one of the strands.

10. Process according to claim 7, wherein the predrawing immediately precedes the inclusion of the predrawn length increment in the rsulting splice by a continuously performed fluid-splicing step.

11. In treatment of textile strands drawable to permanently increased length wherein successive strands of finite length are spliced together and are so drawn in succession, the improvement comprising predrawing a terminal portion of one strand to be spliced to an adjacent undrawn terminal portion of another strand.

12. Strand treatment according to claim 11, wherein the predrawn terminal portion is at an end of a strand preceding the strand with the adjacent undrawn terminal portion.

13. Strand treatment according to claim 11, wherein the predawn terminal portion is at an end of a strand following the strand having the adjacent undrawn terminal portion.

14. Strand treatment according to claim 11, including the steps of juxtaposing the predrawn and undrawn terminal portions in overlapping relationship to one another and then air-splicing the juxtaposed terminal portions together.

15. Strand treatment according to claim 14, including the step of crimping the spliced strands after drawing thereof to permanently increased length.

16. Strand treatment according to claim 15', wherein the crimping step comprises stuflFer crimping, and the successive strands are drawn and crimped successively in continuous manner.

17. Continuous treatment of filamentary textile strands drawable to permanently increased length, wherein successive strands of finite length are spliced together to maintain continuity of operation and are so treated in succession, comprising the steps of predrawing a terminal portion of each strand before splicing it to an undrawn terminal portion of a strand adjacent thereto in the suc cession of strands, juxtaposing the respective terminal portions in overlapping relation to one another and splicing them together, and draw-crimping the spliced strands.

18. Strand treatment according to claim 15, wherein the splicing step is accomplished by fluid-splicing.

19. Strand treatment according to claim 16, wherein the fluid-splicing comprises rotating air circumferentially of the juxtaposed terminal portions and thereby swirling component filaments of the respective strands into spliced interengagement.

References Cited UNITED STATES PATENTS 2,515,172 7/1950 A-bbot 57159 3,082,593 3/1963 Rhyne 57142 XR 3,339,362 9/1967 Dodsen et al 57159 3,379,002 4/1968 Rosenstein 57--159 XR 3,407,583 10/1968 IrWin et al 57159 XR 3,458,905 8/1969 Dodson et al 5722 XR DONALD E. WATKINS, Primary Examiner US. Cl. X.R. 57159 

